Steam-boiler



(No Model.) 4 Sheets-Sheet 1.

GHENGEL STEAM BOILER. No. 577,916. 4 Patented Mar; 2, 1897.

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INVENTOR' 0 6 BY @WMMa ATTORNEYS I wnNESsEsf (No Model 4 Sheets-Sheet 2.

G.E NGEL-.

STEAM BOILER.

No. 577,916. Patented Mar. 2, 1897..

WITNESSES: INVENTOR ww i 755.1% aflfim ATTORNEYS fm: Nonms PEIERS wuovo-umm msumnwn. n. c.

4 Sheets-$11 M 3. V G ENGEL STEAM BOILER.

(No Model.)

No. 577,916. Patented Mar. 2, 1897 INVENTOHV WITNESSES: fla/M a mwm ATTORNEYS" (No Model.) 4 Sheets-Sheet 4.,

G.BNGEL.-J

STEAM BOILER.

No. 577,916. PatentedMar. 2, 1897.

' mvtmon ATTO R N EYS Unitas STATES PATENT OFFICE.

GODFREY ENGEL, OF SOUTH BALTIMORE, MARYLAND.

STEAM-BOILER.

SPECIFICATION forming part of Letters Patent No. 577,916, dated March 2, 1897. Application filed August 4, 1896. Serial No. 601.599. (No model.)

To all whom it may concern.-

Be it known that I, GODFREY EN GEL, a citizen of the United States, residing at South Baltimore, in the county of Anne Arundel and State of Maryland, have invented certain new and useful Improvements in Steam- Boilers or other Similar Apparatus; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates generally to the construction of drums and headers of steam-boilers and other similar apparatus, and particularly to a novel construction thereof whereby a series of straight tubes, such as the generating-tubes of a tubular steam-boiler, may be connected to the cylindrical or otherwisecurved surface of a drum or header at substantially right angles to the walls of the drum or header at the point of connection, although said tubes are not in line with radii of the drum or header, and my invention,while particularly applicable to tubular steam -boilers, is equally applicable to other apparatus employing drums to which are connected a series of tubes.

My invention consists in the novel construction of the drum or header whereby there are provided in curved Walls of such drum or header bosses in the faces of which are apertures for the reception of tubes, such faces bein g substantially at right angles to the tubes.

In steam-boilers and other apparatus exposed to varying pressures and varying temperatures and consisting in Whole or in part of a drum, usually cylindrical, and a series of tubes connected therewith and entering the curved surface of the drum it is usually necessary, in order to insure tight joints, that each tube shall enter this curved surface at substantially right angles thereto. If the boiler has a series of generating-tubes directly connected to the curved surface of a steamdrum, this necessitates the bending of the tubes; but bent tubes are objectionable because it is impossible to introduce scrapers into them through their whole length to remove scale which may have collected and because it is impossible to examine the Whole of the interior of each tube. In replacing the tubes of such boilers also care has to be used to obtain tubes bent to the exact curvature. To avoid the'bendin g of the generating-tubes, manifolds or headers are frequently interposed between the generating-tubes and the steam-drum, and these headers are constructed with flat surfaces. Such a header, if arranged to receive all or a large number of the generating-tubes, is a substantially rectangular box, Which requires extensive bracing, and to be reliable must be built up from boilerplate and must not be cast. To avoid the use of such a header, most tubular steam-boilers are provided with a number of headers, each connecting a comparativelysmall number of generating-tubes with the steam-drum of the boiler; but such headers, by reason of their peculiar shape, can only be constructed economically in most cases by casting, and hence are brittle and unreliable and possess all the other disadvantages inherent in cast metal. Moreover, the number of such sectional headers required usually makes it necessary to provide the stean1-drum with a box or saddle to receive the connecting-nipples from the headers, and this necessitates either the cutting away of the shell of the drum, thus weakening it, or providing the drum with a cast head havingasaddle cast on it. Both of these constructions are objectionable.

The objects of my invention are, first, to so construct the drums and headers of steamboilers and other similar apparatus having curved walls to which tubes are to be connected that faces having apertures for the reception of straight generating-tubes and the like, and which are substantially at right anglesto the tubes, are provided in these walls, without weakening the drums and headers, Without causing the walls to depart materially from their desired curved form,

and Without requiring the use of interior stiffening-braces, and, second, to so construct the drums and headers of steam-boilers that while their Walls retain the general curved form which is necessary for strength and stiffness straight tubes may be used and may be connected to the walls of the drums and headers at substantially right angles thereto, and the drums and headers may be constructed from boiler-plate and without internal bracing or strengthening. These objects are attained in the invention herein described and illustrated in the drawings which accompany and form a part of this application, in which the same reference-numerals indicate the same or corresponding parts, and in which Figure 1 is a sectional elevation of one type of boiler employinginclinedgenerating-tubes and cylindrical headers at the ends thereof, the front headers being connected with a steam-drum at the top. Fig. 2 is a detail elevation of one of the headers 0f the boiler shown in Fig. 1. Fig. 3 is a sectional elevation of another type of steam-boiler, in which the generating-tubes are directly connected with water-drums at the bottom and steamdrums at the top, no headers being used. Fig. 4 is a sectional elevation of another type of boiler, in which the generating-tubes are directly connected with the drums; and Fig. 5 is a detail transverse section of a boilerdrum constructed in accordance with my invention, the particular drum shown being arranged to receive two series of generatingtubes arranged substantially at right angles to each other.

Referring to the drawings, and first to Figs. 1 and 2 thereof, which illustrate a form of tubular steam-boiler employing cylindrical headers constructed in accordance with my invention, 1 is the main steam-drum of the boiler; 2 2, the generating-tubes, connected at one end with a front header or headers 3 and at the rear with a similar header or headers 4. The front header 3 is directly connected to the steam-drum 1, and the rear header is directly connected to the mud-d rum 5 and is connected at the bottom to the steamdrum 1 by a circulating-pipe 7.

In Fig. 1 there are shown but one front and one rear header, with the generating-tubes corresponding thereto. The boiler may consist of one or more elements of this kind joined to a common steam-drum 1 and, if desired, to a common mud-drum 5. The boiler is provided with the ordinary setting and with a furnace and flue-chamber. The headers and 4 are cylindrical and maybe formed from flat plates rolled or pressed into shape and riveted.

The headers and 4 are provided with a number of bosses (3, corresponding in number to the number of generating-tubes connected with the header, and having arranged in steps upon the curved surface of the drum faces at right angles to the generating-tubes in which are apertures into which the ends of the generating-tubes may be expanded. These bosses are formed by stamping or pressing the metal sheets from which the header is made before these sheets are connected together. In order that these bosses may not project farther than is absolutely necessary from the true cylindrical surface of the header, so as not to weaken the header materially, the metal from which these bosses is formed are stamped partly outward from the true cylindrical surface and partly inward. The bosses are separated from each other by portions of the drum having the normal, or, in this case, cylindrical,curvature of the drum. These cylindrical portions of the shell of the drum separating the bosses prevent any deformation of the boiler when under pressure and hold the drum to its proper form. I11 Fig. 5 such a drum or header is shown in section, the particular drum there shown being the steamdrum of a boiler having generating-tubes connected with it on two sides. In forming the bosses, as will be seen in Fig. 5, the metal is bent inward as much as it is bent outward, the result being that these bosses do not cause the drum or head er to depart materially from the true cylindrical form, nor do they so strain the metal as to weaken the drum or header. By this construction, however, the generating-tubes are made to enter the drum or header at right angles to the surface thereof, thereby avoiding oblique joints or the necessity of bending the generating-tubes.

Where arow of tubes connected to the drum is substantially in line with a radius of the drum, it is unnecessary to form in the walls of the drum bosses for the reception of the tubes unless the drum be of extremely small diameter. This is illustrated in Fig. 5, in which the middle tube of each of the two sets of tubes there shown is substantially in line with a radius of the drum and therefore is substantially normal to the cylindrical surface of the drum; but tubes on either side of this central tube are not in line or substantially in line with the radii of the drum, and for their reception it is necessary to form bosses the faces of which are each at an angle to the curved surface of the drum, but are substantially at right angles to the tubes.

The front header 3 of the boiler shown in Fig. 1 is provided on its front side with a similar row of bosses to that which receive the ends of the generating-t ubes, and in these bosses are hand-holes, closed in the common manner, through which the generating-tubes may be examined, cleaned, and replaced, if necessary. It is not ordinarily necessary to provide the rear header 4 with a similar series of hand-holes, but the header is provided with a manhole at the top, through which it may be cleaned. The front header is provided with a similar manhole at the bottom.

The boiler illustrated in Fig. 1 possesses many advantages over the ordinary form of tubular steam boiler employing sectional headers. The headers, being cylindrical, are strong and light, and being made from boilerplate are reliable and may be made quite cheaply. The headers may be made of such diameter that each will receive the ends of four or five or even more vertical rows of generating-tubes, so that a boiler may consist of only one or two or three of the elements shown in Fig. 1, having therefore buta small number of parts and but few openings into v Moreover, because of the the steam-drum.

size of the headers, ample room is afforded for the disengagement of the steam from the water and a considerable water-space is afforded, so that it is not necessary to carry a high water-level in the steam-drum l or to use so large a drum as has been necessary heretofore. When in operation, the water from the boiler circulates from the steamdrum 1 downwardly through the pipe 7 into the bottom of the header 4, and thence upward and through the generating-tubes 2 in to the front header 3 and back to the steamdrum 1 again, the steam disengaging as the water rises.

In Fig. 3 is shown another type of boiler in which the steam and the water drums are constructed in accordance with my invention, no headers being employed. The boiler consists of two water-drums S 8 and two steamdrums 9 9 above the drums 8 8, connected with the water-dru ms by inclined generatingtubes '10, all set within a suitable setting. 11 is the furnace. The furnace-gases circulate upward from the grate-bars to the drums 9 9 and then pass downward along, the inclined generating tubes and through passages formed between partitions 12 12 and 1313 into flues 14 14 at the bottom. The waterdrums 8 8 and the steam-drums 9 9 are constructed in substantially the same manner as are the headers 3 and 4 of the boiler shown in Fig. 1 and the drum shown in Fig. 5, being provided with bosses 6 for the ends of the generating-tubes, which have faces at right angles or substantially at right angles to the generating-tubes.

In Fig. 4 there is shown another type of boiler consisting of three or more waterdrums 14 14 14 and a corresponding number of steam-drums 15 15 15, connected in pairs by generating-tubes 16 and so supported that the generating-tubes are inclined somewhat to the horizontal. The two lower steam-dru ms 15 are each connected with the drum above by a stand-pipe 17, projecting up into said drum to the preferred water-level therefor. The steam-drums 15 15 15 and the water-drums 14 14 14 are provided with independent bosses to receive the ends of the generatingtubes and have faces substantially at right angles thereto, thus avoiding oblique joints or the bending of the generating-tubes. The steam-drums 9 9 of Fig. 3 and 15 15 15 of Fig. 4 are provided with hand-holes opposite the ends of the generating-tubes, through which the tubes may be examined and cleaned. These hand-holes are formed in the flat surfaces of bosses similar to those which receive the ends of the generating-tubes.

It will be observed that in all of the types of boilers herein illustrated and described the use of cast iron or steel parts exposed to steampressure is entirely avoided, while the boilers contain no parts of irregular shape, which, if not cast, can only be formed by elaborate and difficult mechanical processes, but that Straight tubes and simple drums may be used and the headers or drums which receive the ends of the generating-tubes may be constructed almost as easily and cheaply as plain drums.

It is not essential that the tubes connected to the drums and headers in the manner above described shall be precisely at right angles to the faces of the bosses. A slight deviation from the perpendicular is sometimes desir able and is permissible to the same extent that it would be permissible if the tubes were connected to a flat-sided tank. For this reason I have stated in the following claims that the tubes are substantially at right angles to the faces of the bosses.

The drawings of this application show the connection of tubes with the sides .of cylindrical drums and headers. It is obvious,

however, that the invention is not limited in its application to the connecting of tubes with the sides of cylindrical drums, but that tubes may be connected to any curved surface in precisely the same manner by formin gin such surface bosses the faces of which are substantially at right angles to the tubes. The ends of drums frequently are formed from wrought-iron, steel, or similarmetal andhave a spherical or approximately spherical form, in order to secure strengthand stiffness without the use of internal braces. sired to connect tubes to the heads of such drums, the heads may be provided with bosses similar tothose with which the drums and headers illustrated in the drawings are provided. ited to the connection of tubes to the sides of cylindrical drums and headers, but is applicable to the connection of tubes to curved surfaces generally.

By the term boss herein used I mean any protuberant part ofv the wall of a drum or header, having a face provided with an opening for the reception of the end of a tube and which occupies but a comparatively small portion of the circumference and surface of the drum or header, whether said boss be outwardly protuberant or inwardly protuberant or whether it project partly outward and partly inward, as in the form shown in the drawings.

Having thus completely described my invention, whatI claim, and desire to secure by Letters Patent, is--- 1. A drum for steam-boilers and similar apparatus, adapted to be directly connected to a series of tubes, having a curved surface, and having in said surface a series of independent bosses, the faces of which are pro vided with openings for the reception of the ends of the tubes and are substantially at right angles to their tubes, said bosses being arranged in steps upon the surface of the drum, and being separated from each other by curved portions of the drum, by which the form of the drum is retained, substantially as described.

2. A drum for steam-boilers and similar ap- If it be de- My invention therefore is not lin1- paratus, adapted to be directly connected to a series of tubes, and consisting of a generally cylindrical drum, in the cylindrical surface of. which are a series of independent bosses having faces, which are provided with openings for the reception of the tubes and are substantially at right angles to their tubes, said bosses being arranged in steps upon the cylindrical surface of the drum and being separated from each other by cylindricallycurved portions of the drum, by which the form of the drum is retained, substantially as described.

3. A drum for steam-boilers and similar apparatus, adapted to be directly connected to a series of tubes, and consisting of a generally cylindrical drum having stamped in its sides a series of independent bosses projecting partly inward and partly outward from the cylindrical shell of the drum, and having faces which are provided with openings for the reception of the tubes and are substantially at right angles to their tubes, said bosses being arranged in steps upon the cylindrical surface of the drum and being separated from each other by cylindrically-curved portions of the drum, by which the form of the drum is retained, substantially as described.

4. In a boiler, the combination,with a series of generating-tubes, of a drum adapted to be directly connected to said tubes, having a generally cylindrical form, and provided with a series of independent bosses, the faces of which are provided Wit-h openings for the reception of the tubes and are at substantially right angles to their tubes, said bosses being arranged in steps upon the cylindrical surface of the drum, and being separated from each other by cylindrical curved portions of the drum, by which the form of the drum is retained, substantially as described.

5. In a boiler,the combinatiomwith a steamdrum and a series of inclined generatingtubes, of front and rear headers for connecting said tubes at the front and rear to each other and to the steam-drum, said headers being generally cylindrical in form, and having in their sides series of independent bosses, the faces of which are provided with openings for the reception of the tubes and are substantially at right angles to their tubes, said bosses being arranged in steps upon the cylindrical surface of the drum, and being separated from each other by cylindricallycurved portions of. the drum, by which the form of the drum is retained, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

GODFREY ENGEL.

Witnesses:

PHIL. L. HERRMAN, GEO. H. WATGHMAN.

meow nl Lcuclb'l'mcnrwu. un gu-ucylindrical drums and headers.

DISCLAIMER.

57 7,916.- Godfrey Engel, South Baltimore, Md. STEAM-BOILERS. Patent dated March 2;

V 1897. Disclaimer filed October 1, 1907, by assignee.

, Enters this disclaimer- To those parts of the specification which are contained in lines 83 to 106, page 3, of the printed specification, being the following words, to wit:

The drawings of this application show the connection of tubes with the sidesof It is obvious, however, that the invention is not limited in its application to the connecting of tubes with the sides of cylindrical drums, but that tubes may be connected to any curved surface in precis ly the same manner by forming in such surface bosses the facesof which are substantially at right angles to the tubes. The ends of drums frequently are formed from wrought-iron, steel, or similar metal and have a spherical or approximately spherical form, in order to secure strength and stifiness without the use of internal braces. If it be desired to connect tubes to the heads of such drums, the heads may be provided with bosses similar to those with which the drums and headers illustrated in the drawings are provided. My invention therefore is not limited to theconnection of tubes to the sides of cylindrical drums and headers, but is applicable to the connection of tubes to curved surfaces generally.[ Ofiim'a'l Gazette, October 8, 1.907 4 i 

